The present invention is related to a safety system and more particularly to a warning sign safety systems for entering and exiting garage doors and entrances.
There is known Canadian Patent 2,015,205 related to a safety system to exiting garage doors having a door operator with a main control circuit, electrical motor and a reversible drive train, wherein the main control circuit provides one of four modes of operation of door opening, door stopped open, door closing and door stopped closed.
There is also known Canadian patent 2,312,311 related to a garage door status indicator kit comprising a sensor for emitting an output signal if the garage door is open, an indicator means mountable on the wall in the garage interior for receiving the output signal and power source connecting means to connect the sensor and indicator.
There is also known U.S. Pat. No. 5,529,274 related to a remote control motor-driven drum to wind and unwind a cord which holds a self-balancing sign suspension system, wherein the motor, which is reverable, is remotely controlled either by wires leading between the motor and a switch, or by radio control.
There is a continuous problem in small and large warehouses with one or many garage doors: the doors are frequently damaged by big vehicles such as trucks, lift trucks, fire trucks or buses as the vehicles go through the doors. According to unpublished statistics, annual repair bills for this damage may run from $250,000 to over $1 million per warehouse. These doors can be located in such places as municipal warehouses or distribution points of multi-national soft-drink and breweries all over North America. Besides, the damage is not only done to the doors, but to the trucks as well; each accident could cost around $2,000.00 per truck. Considering the fact that, on average, 30 to 100 accidents are registered per year for each large warehouse, this cost must be multiplied accordingly.
In addition, if the warehouse is located in a cold climate where, during the winter, the temperature could easily fall below xe2x88x9220xc2x0 C. (12xc2x0 F.) it is necessary to use standby heating systems to maintain the proper ambient indoor temperature (at least at 15xc2x0 C.) to prevent cold air from spoiling the stored goods until the damaged door is repaired. In general, it may take 2-3 days to fix the damaged door, and the owner of the warehouse is forced to spend substantial funds for the additional heating of this area of warehouse.
The reason the vehicles cause damage to the doors is due to the fact that when crossing the door entrance, whether going inside or outside, the driver""s primary line of sight is usually in front of him to make sure that he does not hit a pedestrian. Commonly in the industry, there are red/green warning lights controlled by different types of vehicle detectors connected to a control panel. Detectors, such as photocells, magnetic activators or other types, are provided to see the vehicle to activate the door to open. While the door is still not completely open, the red light is xe2x80x9conxe2x80x9d to keep the driver from moving. The light turns green only when the door is completely open, indicating that the driver is free to pass without any restriction.
However, very often the driver does not pay attention to these red/green lights because they are placed not in his primary line of sight in front of him because the warning lights are usually installed on one or both sides of the garage door. This is a secondary line of sight of the driver. Another reason for such accidents is due to daylight: when the driver is exiting the garage during the day, it is darker inside than outside; the daylight blinds the driver, and he has difficulty seeing any warning signals. At many locations, vehicles are sensed when they are less than 10 feet from the door. At 5 km/hour, the driver does not have enough reaction time to stop before crashing into the door. Also, if the driver is in the middle of a 25-foot wide door and it starts to close, he will hardly see the warning lights on the side of the entrance. Some light systems are activated by a switch that needs a 6xe2x80x3 travelling distance from the door before the light turns red.
The object of the present invention is to eliminate this problem and to substantially reduce expenses caused by those accidents.
The present invention uses an innovative system provided to hold a warning sign that will be lowered down to be suspended in front of the truck at the driver""s eye level. Such advantageous positioning of the warning sign in the primary line of sight will be definitely seen by the driver and will warn him that the door is not completely open. The warning sign may be activated by any kind of detectors. The same detector may be used for the activation of the garage door as well. The warning sign is lowered when the door starts to close, and stays there while the door is opening. When the door is completely open, the warning sign will be raised, thus allowing the driver to exit. Neither the warning sign nor the door will be lowered as long as the vehicle is in the vicinity of the door to eliminate accidental damage to the door. Once the door entrance is free, the warning sign will go down, and only when it is completely down will the door start to close. Optionally, it is possible to install a special relay to provide an additional delay right after the sign is down to increase the reaction time for the driver before the door will start to close. As a result, the warning sign will be suspended in the primary line of sight of the driver in case the door will start to close or is not completely open, thus giving the driver more time to react.